|  | Definition 1 (≥0.2) |  | Definition 2a (≥0.35) |  | Definition 3 (≥0.7) | |||
---|---|---|---|---|---|---|---|---|---|
Definition 1 (≥0.2 IU/ml) | Zambia n (%) | South Africa n (%) | Definition 2 (≥0.35 IU/ml)a | Zambia n (%) | South Africa n (%) | Definition 3 (≥0.7 IU/ml) | Zambia n (%) | South Africa n (%) | |
Positive | Â | 735 (54) | 626 (76) | Â | 669 (49) | 574 (70) | Â | 599 (44) | 504 (61) |
 Nil | ≤8.0 |  |  | ≤8.0 |  |  | ≤8.0 |  |  |
 TBAgNil | ≥0.2 & (≥25% of Nil value) |  |  | ≥0.35 & (≥25% of Nil value) |  |  | ≥0.7 & (≥25% of Nil value) |  |  |
Negative | Â | 445 (33) | 182 (22) | Â | 495 (36) | 230 (28) | Â | 551 (40) | 297 (36) |
 Nil | ≤8.0 |  |  | ≤8.0 |  |  | ≤8.0 |  |  |
 TBAgNil | < 0.2 or < 25% Nil |  |  | < 0.35 or < 25% Nil |  |  | < 0.7 or < 25% Nil |  |  |
 MitogenNil | ≥0.5 |  |  | ≥0.5 |  |  | ≥0.5 |  |  |
Indeterminateb | all other values | 185 (14) | 14 (2) | all other values | 201 (15) | 18 (2) | all other values | 215 (16) | 21 (3) |